HomeMy WebLinkAbout20081615 Ver 2_Public Notice_20100831US Army Corps
Of Engineers
Wilmington District
�8- I LP
PUBLIC NOTICE
Issue Date: August 31, 2010
Comment Deadline: September 30, 2010
Corps Action ID No: SAW -2006-40808
All interested parties are hereby advised that the Wilmington District, Corps of Engineers
(Corps) has received a request from the Town of Topsail Beach, North Carolina (Town)
seeking to modify its June 15, 2009 Department of the Army (DA) Permit authorizing the
Topsail Beach Interim (Emergency) Beach Fill Protection Project. Specifically, the
Town has requested to eliminate the open ocean borrow area (Borrow Area "X") as a
sand source and include inshore borrow areas within the existing federal navigation
channels (Topsail Creek, Topsail Creek Crossing, and Banks Channel) and Corps
maintained dredge material placement sites (DA 189 & DA203) located in Topsail Sound
inland of the Town of Topsail Beach.
Specific plans and location information are described below and shown on the attached
plans. This Public Notice and all attached plans are also available on the Wilmington
District Web Site at www.saw.usace.armv.mil/wetlands
Applicant: Attn: Tim Holloman, Town Manager
Town of Topsail Beach
820 S. Anderson Boulevard
Topsail Beach, North Carolina 28465 4 5
AGENT (if applicable): Chris Gibson, PE
Gahagan and Bryant Associates of NC
295-A North Green Meadows Drive
Wilmington, North Carolina 28405
Authority
The Corps will evaluate this request and a decide whether to issue, conditionally issue, or
deny the proposed modification pursuant to applicable procedures of Section 404 of the
Clean Water Act (33 USC 1344) and Section 10 of the River and Harbors Act.
Location
The project site is located on the southern end of Topsail Island, within the Town Limits
of the Town of Topsail Beach. Topsail Island is located in southeast North Carolina and
is the central island along Onslow Bay. The Town is bounded to the north by Surf City,
the West by Topsail Sound and south by the federal maintained New Topsail Inlet.
The island is accessible to the public by highways 50 and 210 with Highway 50 being the
only entry road to the Town of Topsail Beach. The geographic coordinates are Latitude
34022'10" N; Longitude 77037'30"W (NAD83). The proposed modified borrow areas
are located west of the island.
Background
The Town of Topsail Beach has experienced substantial shoreline erosion, exacerbated
by multiple direct and near direct encounters with tropical storm systems. In order to
mitigate loss of property and infrastructure, a Federal Storm Damage Reduction Project
was authorized under WRDA 1992. In Nov 1989 the Corps released a Final
Environmental Impact Statement (FEIS) detailing the proposed federal beach
nourishment project and preferred borrow sources. Federal funds were not secured for
the project however, and the project became inactive when the Town withdrew its
support in 1994 due to funding limitations. A General Reevaluation report of the federal
project was completed by the Wilmington District and the combined GRR/EIS was
released for final public review in Aug 2008.
Due to the expected timeline associated with Re -Authorization of the federal project, the
Town applied for a DA permit to conduct a one-time, privately funded interim beach
nourishment project. The Corps released a supplement to the FEIS (SFEIS) detailing the
proposed project on April 10, 2009. Several borrow source alternatives were considered
during the development of the SFEIS including the existing federal navigation channels
(Topsail Creek, Topsail Creek Crossing, and Banks Channel) and existing federal
disposal areas. It was determined, based on the information available at the time, that
the volume of material that could be removed from within the limits of the authorized
navigation channel was not sufficient to meet the interim shore protection needs. It was
also determined that the disposal areas along the Atlantic Intracoastal Waterway (AIWW)
did not contain enough material meeting the North Carolina sediment criteria to complete
the proposed nourishment project. Thus, alternatives involving these options were not
carried forward.
A Record of Decision (ROD) completing the NEPA process was signed on June 12,
2009. A DA permit was issued to the town on June 15, 2009 to place approximately
1,000,000 cubic yards of beach quality sand along the 24,700 linear feet of developed
shoreline on Topsail Island from an ocean borrow area, designated as "Borrow Area X",
located immediately southeast of New Topsail Inlet.
The unexpectedly high bids received during the contract procurement process in 2009
and delays in project implementation prompted the Town to re -investigate alternative
sand sources. As a part of this effort, the Town contracted Gahagan & Bryant Associates,
Inc (GBA) to conduct more detailed vibracore surveys of disposal areas along the AIWW
as well as some areas within the existing federal channels. GBA also examined recent
hydrographic surveys of the existing federal channels. This new information revealed
2
that removal of the material now accumulated in the existing federal channels within
Topsail Creek, Topsail Creek Crossing, and Banks Channel combined with removal of
suitable material from within two Federal disposal areas along the AIWW would generate
adequate volumes of material suitable to complete the beach nourishment project.
The town has now proposed to modify its DA permit to eliminate the offshore area,
"Borrow Area V as a sand source for the project and instead utilize material from the
above mentioned federal channels and disposal areas. The Town has asserted that
utilizing these inland borrow sources would result in substantial cost savings with less
environmental impacts and would fully meet the Town's interim beach nourishment
needs. To minimize environmental impacts, the Town proposes to limit borrow activities
to only that material accumulated within the authorized dimensions of the Federal
navigation channels and within two active Corps disposal areas, owned by the State of
North Carolina, and located within the Corps' AIWW easement. Regularly conducted
federal channel maintenance activities are currently authorized to utilize portions of the
proposed beach nourishment project area for disposal.
Applicant's Stated Purpose
According to information provided by the applicant, the purpose of the proposed
modification is to minimize project costs and environmental impacts while providing an
equal level of shoreline protection as the currently authorized project. The proposed
permit modification does not seek to alter the permitted beach nourishment design, but
only to modify the location from which the material will be acquired.
Project Description
Due to an urgent need for a beach nourishment project along the oceanfront of Topsail
Beach, beach fill construction is proposed for the fall of 2010. This project will involve a
multi -faceted approach, targeting several key borrow areas to achieve the quantity and
quality of material necessary to meet and exceed state standards in constructing a viable
beach. The proposed plan includes 800,000-975,000 cubic yards (cy) of material to be
placed along approximately 25,000 ft of Topsail Beach's oceanfront shoreline. Based on
the characteristics of the material found in the borrow areas, approximately 900,000 to
1,050,000 cy of material will be required to build the designed beach template.
Borrow Area Locations
Each proposed borrow area is situated in the back barrier area or landward of the barrier
island atop of which the Town of Topsail Beach resides. These sites include portions of
the Corps maintained Disposal Areas DA -189 and DA -203. Other targeted sites include
areas within the federally maintained navigation channels of Topsail Creek, Banks
Channel, and the Atlantic Intracoastal Waterway (AIWW). Four main segments have
been delineated along the oceanfront to receive dredge material during construction
phase. To reduce project cost, streamline workflow, and optimize the sediment source
budget each segment of the oceanfront will receive material from a specified borrow area.
3
Currently, the proposed oceanfront fill segment boundaries are conditional and subject to
change based on the contractor's schedule of work.
Borrow Material Characteristics
The applicant has submitted to the Corps the findings from the geotechnical
investigations conducted by GBA. The borrow areas were divided into four (4) sub-
sections for evaluation, DA -189, DA -203, the Atlantic Intracoastal Waterway, and
Topsail Creek/Banks Channel. Each sub -section was investigated and analyzed as an
independent site as well as part of the entire source. GBA performed the investigation in
both DA -203 and DA -189 twice, once as a reconnaissance level study and once utilizing
the standards prescribed in by the North Carolina Coastal Resource Commission (CRC)
in administrative code 15A NCAC 07H.0312. Both methodologies produced nearly
identical results.
To ensure beach fill material placed on a beach is compatible with the beach, The North
Carolina Coastal Resources Commission (CRC) adopted a state Sediment Criteria Rule
for borrow material (15A NCAC 07H .0312). This rule also limits the amount of silt (<
0.0625 mm) to 5% above the native beach material and gravel (>4.76 mm) to 5% above
native beach material. Also, the percent of the borrow material by weight between 4.76
mm and 2.0 mm cannot exceed the native by more than 5%. Characterization of each
borrow site requires no less than 10 evenly spaced cores or one core per 10 acres,
whichever is greater. These technical standards are discussed further in the FSEIS,
Section 5.15.7.1. The beaches of Topsail Beach, have an average gravel content of
0.17%, the upper limit of gravel is 5.17%. The silt content of the native material is
0.94% resulting in a maximum allowable silt content from the borrow areas of 5.94%.
The material within each borrow area sub -section meets the Sediment Compatibility
Criteria defined by the CRC for silt, shell gravel and carbonate content. The material has
similar mean and median grain size to that of the currently planned borrow area as shown
in the following table.
Table 1:
Inland Borrow Area
Composite Summary Table
Topsail 2010 Whrar_erps
Borrow
Volume
Mean
Mean
Median
Median
PHI
Area
(CY)
(mm)
(phi)
(mm)
(phi)
Sorting
Silt
Shell
AIWW
91,000
0.18
2.48
0.18
2.46
0.33
0.43
7.8
Topsail
Creek
107,000
0.24
2.05
0.22
2.17
0.65
0.21
6.8
DA203
1 460,000
0.19
2.42
0.18
2.48
0.50
4.13
4.8
DA189
387,000
0.18
2.50
0.17
2.59
0.52
5.73
4.5
Inland
1.045
Borrow
MY
0.19
2.42
0.18
2.49
0.51
4.00
5.2
4
Table 2:
Borrow material characteristics compared to native material
Borrow
Volume
Mean
Mean
Median
Median
PHI
%
%
Area
(CY)
(mm)
(phi)
(mm)
(phi)
Sorting
Silt
Shell
Topsail
N/A
0.24
2.05
0.21
2.23
0.86
0.94
11
Native
Inland
1.045
0.19
2.42
0.18
2.49
0.51
4.00
5.2
Sources
MY
X
1.5
0.20
2.31
0.16
2.63
1.21
2.17
5.0
MY
Dredging Logistics
The project will involve the use of a hydraulic dredge in the 16"-20" class. Planned
pipeline routes will follow corridors used previously during historic dredge and
nourishment events in the local area. Pipelines will cross over the island at specific
approved use areas previously used by the Corps to access the beach with dredge
pipeline. A suitable pipeline route for dredging DA -189 and discharging fill to the
oceanfront beach will follow Harvey's Cut and cross over the island at Queen's Grant.
Similarly, the pipeline route associated with dredging practices to the south at DA -203
and in the federal navigation channels will follow Topsail Creek and cross over the island
at Smith Avenue.
Locations of proposed cuts into each DA are based on minimizing environmental impacts
on marsh vegetation surrounding these sites and also consider draft depths that dredges of
this class require. With the exception of the area designated for cut -in access to a DA, no
vegetation that exists currently outside the dikes or surrounding the DA will be impacted
by project construction efforts. Established vegetation within the dikes of each DA will
be cleared as needed for the dredging activity.
Dredge Access to Borrow Areas
Access to all borrow areas is via the AIWW. Typically to access and remove material
from a confined disposal facility, a contractor will dredge a temporary access channel
from the main channel into the site. The material will be removed by normal hydraulic
dredging methods. Then, after project completion and dredge is demobilization, the
access channel is filled in and the levee restored by mechanical earth moving equipment
so that the site is again operational. This method will be utilized for excavation of DA -
203.
For DA -189, the perimeter of the island has been identified as a Primary Nursery Area
(PNA). The North Carolina use standards, specifically 15A NCAC 07H.208 (b) (1),
preclude new dredging in a PNA. Equipment is allowed to be transported over a PNA or
marsh so long reasonable and prudent measures are utilized to minimize the disturbance
to the areas. Thus, for DA -189, construction equipment (i.e. dredge, induction pump, or
other method of slurrying material) will be transported into the DA without excavating
any area between the mean high water line and the federal navigation channel.
5
The proposed dredge access method (subject to minor changes) into DA -189 is as
follows:
1. A "starter pond" of sufficient length, width, and depth for the dredge to begin
operations will be excavated inside the existing perimeter levees.
2. At the access point, the perimeter levee will be graded down to slopes and elevations
that would allow skids or mats to be placed over the marsh and levee.
3. Skids or mats will be laid over the marsh and the dredge will be pulled across the
skids, over high ground into the starter pond.
4. The dredge will perform dredging operations with slurry water being provided by
pumps or siphon.
5. The dredge will be demobilized using steps 3 & 2, with the levees being restored to
elevations consistent with the design.
This procedure will avoid and minimize to the maximum extent possible the potential
impacts to the PNA adjacent to DA -189.
Clearing of Disposal Areas
With the exception of the areas designated for cut -in or access to a DA, no vegetation that
exists currently outside the dikes or surrounding the DA will be impacted by project
construction efforts. Established vegetation within the dikes of each DA will be cleared
and burned if it resides above proposed dredge material. On, DA -189, vegetation will be
cleared and relocated to the northern extent of the disposal site to be burned prior to
dredging efforts. On DA -203, little to no clearing of vegetation is expected to be
necessary in the proposed area of disturbance.
Levee Reconstruction
Once dredging operations are completed in these disposal areas, both DA sites will be
restored. Material unsuitable for beach fill from the DA's will be used to rebuild the
portions of dike affected by this project. Slopes of 2:1 will be constructed for all dikes
surrounding the disturbed portion of each DA.
An existing outfall pipe and weir box assembly currently exists on DA -189. In order to
utilize this existing assembly, a trench will be excavated extending from the weir box and
that material then used to rebuild the previously penetrated dike. DA -203 will have a
new outfall pipe and weir box assembly constructed to meet USACE and DCM
regulations for a CDF. Approximately 250,000-300,000 cy of capacity will be created
for the USACE in each DA as a result of dredging these borrow sites for this project.
Beach Construction
Construction parameters of the beach profile and shoreline extent to be nourished, along
the oceanfront fill area of Topsail Beach, will follow the authorized beach plan as
on
described in the SFEIS and ROD. Beach slope (15:1) and berm elevation (6.0 ft
NAVD88) will generally follow the typical construction profile, as authorized. .
Project Impacts
The material within the proposed borrow areas has similar characteristics to the material
found in Borrow Area X and is expected to behave similarly once placed on the beach.
Therefore, no new impacts are anticipated within the permitted beachfill area. The
proposed modification will totally avoid previously authorized impacts to 127 acres of
Essential Fish Habitat (EFH) impacts within Borrow Area X.
The proposed modification will result in approximately 0.05 acres of impacts to sandy
bottom habitat associated with the dredge cut into DA -203. The proposed method to
access DA -189 precludes the necessity to excavate adjacent Primary Nursery Areas
(PNA). The proposed project will also include dredging approximately 67 acres of
bottom within the regularly maintained federal channel segments. All dredging within
the federal channel segments will be restricted to the within the currently authorized
channel dimensions. Maintenance dredging of Banks Channel, Topsail Creek, and the
AIWW is conducted by the Corps approximately every three to four years. Based on
current conditions, the Corps is preparing for maintenance activities in these channels in
Fiscal Year (FY) 2011.
Other Required Authorizations
The Corps will generally not make a final permit decision until the North Carolina
Division of Water Quality (NCDWQ) issues, denies, or waives State certification
required by Section 401 of the Clean Water Act (PL 92-500). In addition, pursuant to 33
CFR 325.2(b)(2), the Corps cannot issue a permit for the proposed work until the
applicant has demonstrated and the North Carolina Division of Coastal Management
(NCDCM) has concurred that the proposed activity complies with and will be conducted
in a manner that is consistent with the approved North Carolina Coastal Zone
Management Program. This consistency determination may come in the form of a
Coastal Area Management Act (CAMA) permit.
Essential Fish Habitat
This notice initiates the Essential Fish Habitat (EFH) consultation requirements of the
Magnuson -Stevens Fishery Conservation and Management Act. The Corps has not made
a determination if the proposed modification to the project will or will not adversely
impact EFH or associated fisheries managed by the South Atlantic or Mid Atlantic
Fishery Management Councils or the National Marine Fisheries Service. Based on the
applicant's submitted information the proposed modification will result in a substantial
(99.5%) reduction in direct impacts to EFH over the currently permitted project.
7
Cultural Resources
The Corps has consulted the latest published version of the National Register of Historic
Places and is not aware that any registered properties, or properties listed as being
eligible for inclusion therein are located within the project area or will be affected by the
proposed work. Presently, unknown archeological, scientific, prehistoric, or historical
data may be located within the project area and/or could be affected by the proposed
work.
Endangered Species
The Corps has reviewed the project area, examined all information provided by the
applicant and consulted the latest North Carolina Natural Heritage Database. Based on
available information, the Corps has determined pursuant to the Endangered Species Act
of 1973 (ESA), that the proposed project may affect federally listed endangered or
threatened species or their formally designated critical habitat. A Biological Assessment
(BA) has been prepared and coordinated with the United States Fish and Wildlife Service
(USFWS) and the National Marine Fisheries Service (NMFS) pursuant to Section 7 of
the Endangered Species Act of 1973, as amended. This assessment determined that the
proposed action may affect but will not likely adversely affect the piping plover and the
seabeach amaranth. Due to timing of the project and precautions taken during its
implementation, other Federally listed endangered or threatened species should not be
affected. Consultation under Section 7 of the ESA will be initiated and no permit will be
issued until the consultation process is complete.
Evaluation
The decision whether to modify the existing permit will be based on an evaluation of the
probable impacts, including cumulative impacts, of the proposed activity on the public
interest. That decision will reflect the national concern for both protection and utilization
of important resources. The benefit which reasonably may be expected to accrue from
the proposal must be balanced against its reasonably foreseeable detriments. All factors
which may be relevant to the proposal will be considered including the cumulative effects
thereof; among those are conservation, economics, aesthetics, general environmental
concerns, wetlands, historic properties, fish and wildlife values, flood hazards, flood plain
values (in accordance with Executive Order 11988), land use, navigation, shoreline
erosion and accretion, recreation, water supply and conservation, water quality, energy
needs, safety, food and fiber production, mineral needs, considerations of property
ownership, and, in general, the needs and welfare of the people. For activities involving
the discharge of dredged or fill materials in waters of the United States, the evaluation of
the impact of the activity on the public interest will include application of the
Environmental Protection Agency's 404(b)(1) guidelines.
Commenting Information
The Corps of Engineers is soliciting comments from the public; Federal, State and local
agencies and officials, including any consolidated state viewpoint or written position of
the Governor; Indian Tribes and other interested parties in order to consider and evaluate
the impacts of this proposed activity. Any comments received will be considered by the
Corps of Engineers to determine whether to issue, modify, condition or deny a permit for
this proposal. To make this decision, comments are used to assess impacts on
endangered species, historic properties, water quality, general environmental effects and
the other public interest factors listed above. Comments are used in the preparation of an
Environmental Assessment (EA) and/or an Environmental Impact Statement (EIS)
pursuant to the National Environmental Policy Act (NEPA). Comments are also used to
determine the need for a public hearing and to determine the overall public interest of the
proposed activity.
Any person may request, in writing, within the comment period specified in this notice,
that a public hearing be held to consider the application. Requests for public hearings
shall state, with particularity, the reasons for holding a public hearing. Requests for a
public hearing shall be granted, unless the District Engineer determines that the issues
raised are insubstantial or there is otherwise no valid interest to be served by a hearing.
Written comments pertinent to the proposed work, as outlined above, will be received
by the Corps of Engineers, Wilmington District, until 5pm, September 30, 2010
Comments should be submitted to Dave Timpy, Project Manager , 69 Darlington
Avenue, Wilmington, N.C. 28403.
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LOCATION
PROJECT